Related Experiment Video
Updated: Feb 4, 2026
07:03
Assessment of Motor Balance and Coordination in Mice using the Balance Beam
Published on: March 10, 2011
48.6K
CcpA Coordinates Growth/Damage Balance for Streptococcus pyogenes Pathogenesis
Elyse Paluscio1,2, Michael E Watson1,3, Michael G Caparon4
1Department of Molecular Microbiology, Washington University School of Medicine St Louis, St. Louis, MO, 63110-1093, United States.
Scientific Reports
|September 26, 2018
Summary
Pathogens balance growth and damage; Streptococcus pyogenes's Carbon Catabolite Protein A (CcpA) regulates this. Mutants showed CcpA controls virulence, impacting infection and colonization differently.
Area of Science:
- Microbiology
- Pathogenesis
- Bacterial Genetics
Background:
- Pathogens must balance replication and host damage for optimal fitness.
- Streptococcus pyogenes utilizes Carbon Catabolite Protein A (CcpA) to regulate metabolism and virulence.
- CcpA's role in coordinating growth and damage is crucial for S. pyogenes pathogenesis.
Purpose of the Study:
- To investigate the role of CcpA in balancing bacterial growth and host tissue damage during infection.
- To compare the virulence of wild-type S. pyogenes with CcpA-deficient and constitutively active CcpA mutants.
- To elucidate how CcpA influences pathogenesis in different infection models.
Main Methods:
- Utilized two distinct murine models: acute soft tissue infection and long-term asymptomatic mucosal colonization.
- Generated and compared S. pyogenes mutants: one lacking CcpA and another with a constitutively DNA-binding CcpA (CcpAT307Y).
- Assessed bacterial virulence, tissue burden, and host damage in both models.
Main Results:
- Both CcpA mutants exhibited altered virulence compared to wild-type.
- Loss of CcpA led to reduced growth in tissues, decreased damage, and faster bacterial clearance.
- Constitutive CcpA activity resulted in high bacterial loads and prolonged carriage with diminished tissue damage.
Conclusions:
- CcpA is a master regulator controlling the balance between bacterial growth and host tissue damage.
- The activity of CcpA actively modulates pathogen fitness and virulence strategies.
- S. pyogenes virulence network topology couples carbon metabolism with growth/damage balance, influencing pathogenesis.
Related Concept Videos
02:36Cells Coordinate Growth and Proliferation
5.1K
Cell size is a significant factor impacting cellular design, function, and fitness. There exists some internal coordination by which cells double their masses before division, thus, achieving homeostasis. Coordination between cell growth and proliferation depends on the checkpoints in between cell cycle phases. Loss of coordination or failure in the checkpoint mechanism can drive the cell to uncontrolled growth and loss of cellular function. Like dividing cells that coordinate cellular growth,...
5.1K
02:57Coordination Number and Geometry
19.0K
For transition metal complexes, the coordination number determines the geometry around the central metal ion. Table 1 compares coordination numbers to molecular geometry. The most common structures of the complexes in coordination compounds are octahedral, tetrahedral, and square planar.
19.0K
02:54Coordination Compounds and Nomenclature
26.8K
In most main group element compounds, the valence electrons of the isolated atoms combine to form chemical bonds that satisfy the octet rule. For instance, the four valence electrons of carbon overlap with electrons from four hydrogen atoms to form CH4. The one valence electron leaves sodium and adds to the seven valence electrons of chlorine to form the ionic formula unit NaCl (Figure 1a). Transition metals do not normally bond in this fashion. They primarily form coordinate covalent bonds, a...
26.8K
02:33Lattice Centering and Coordination Number
11.6K
The structure of a crystalline solid, whether a metal or not, is best described by considering its simplest repeating unit, which is referred to as its unit cell. The unit cell consists of lattice points that represent the locations of atoms or ions. The entire structure then consists of this unit cell repeating in three dimensions. The three different types of unit cells present in the cubic lattice are illustrated in Figure 1.
Types of Unit Cells
Imagine taking a large number of identical...
Types of Unit Cells
Imagine taking a large number of identical...
11.6K
02:58Balancing Redox Equations
62.2K
Electrochemistry is the science involved in the interconversion of electrical and chemical reactions. Such reactions are called reduction-oxidation, or redox reactions. These important reactions are defined by changes in oxidation states for one or more reactant elements and include a subset of reactions involving the transfer of electrons between reactant species. Electrochemistry as a field has evolved to yield sufficient insights on the fundamental principles of redox chemistry and multiple...
62.2K
01:21Equations of Motion: Rectangular Coordinates and Cylindrical Coordinates
777
Understanding the motion of particles is a fundamental aspect of classical mechanics, and the choice of the coordinate system plays a pivotal role in unraveling the complexities of their dynamics.
When a particle moves relative to an inertial frame, the equations of motion can be expressed using rectangular components. If the motion is confined to the x-y plane, the equations having the x and y coordinates only can be used to simplify the mathematical representation.
However, when particles...
When a particle moves relative to an inertial frame, the equations of motion can be expressed using rectangular components. If the motion is confined to the x-y plane, the equations having the x and y coordinates only can be used to simplify the mathematical representation.
However, when particles...
777